Vortex reducing device for a gas turbine engine

ABSTRACT

A gas turbine engine has a vortex reducing device therein that includes a retainer and paddles. The retainer is arcuate in shape and has a plurality of circumferentially spaced slots that extend through it. The paddles are circumferentially spaced about the retainer and extend outward thereform. Each paddle is disposed between adjacent slots.

BACKGROUND

The present invention relates to gas turbine engines, and moreparticularly, to gas turbine engines with anti-vortex devices.

Anti-vortex tubes (also know as secondary air tubes or vortex reducingtubes) are known in the art, and are commonly disposed within the highpressure compressor section of gas turbine engines. The tubes direct airbled from a core flowpath radially into a bore of the high pressurecompressor adjacent the turbine engine's shaft(s). As is known,anti-vortex tubes are used to achieve a desired temperature and pressureprofile within the engine for performance purposes. The anti-vortextubes are also used for cooling and other purposes including scrubbingcompressor disks, providing buffer air to bearing compartments, anddirecting cooling airflow to portions of the gas turbine engine'sturbine section.

Existing anti-vortex tubes are assemblies that commonly include multipleparts such as snap rings and retaining rings in addition to individualtubes. Parts such as snap rings and retaining rings are used to couplethe tube assembly to adjoining compressor disks. Such multiple partassemblies add weight to the turbine engine and can add unwantedcomplexity to the assembly/disassembly processes. For example, a detailbalancing of the anti-vortex tubes is done when all the components areassembled together. The balancing requires that each individual tube andtube receiving part be numbered in the event of disassembly to ensureproper balancing of thermal/mechanical stresses upon reassembly.

SUMMARY

A gas turbine engine has a vortex reducing device therein that includesa retainer and paddles. The retainer is arcuate in shape and has aplurality of circumferentially spaced slots that extend through it. Thepaddles are circumferentially spaced about the retainer and extendoutward thereform. Each paddle is disposed between adjacent slots.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a cross-section of a rotor section of a high pressurecompressor for a gas turbine engine.

FIG. 2 is an enlarged cross-section of a vortex reducing device mountedto a compressor disk.

FIG. 3 is a perspective view of the vortex reducing device of FIG. 2.

FIG. 3A is an enlarged perspective view of a paddle and slots of thevortex reducing device of FIG. 3.

FIG. 4 is a perspective view of another embodiment of the vortexreducing device.

FIG. 4A is an enlarged perspective view of a paddle and slots of thevortex reducing device of FIG. 4.

FIG. 5 is a perspective view of yet another embodiment of the vortexreducing device.

FIG. 5A is an enlarged perspective view of a paddle and slots of thevortex reducing device of FIG. 5.

DETAILED DESCRIPTION

FIG. 1 shows a rotor portion of a high pressure compressor 10 for a gasturbine engine 12 with stator portions within the high pressurecompressor 10 not illustrated. The gas turbine engine 12 includes blades14A-14H, disks 16A-16H, a shaft 18, and a vortex reducing device 20.Blades 14A-14H are disposed along a core flowpath 22 (indicated with adirection arrow). Disks 16A-16H extend from blades 14A-14H into a bore24 of high pressure compressor 10 adjacent engine centerline C_(L) andshaft 18. Disks 16A-16H are disposed to form compressor disk interspace26A-26H therebetween.

High pressure compressor 10 and gas turbine engine 12 are ofconventional construction and operate in a manner well known in the art.In particular, air passes from a forward fan section (not shown) of gasturbine engine 12 through a low pressure compressor section (not shown)to high pressure compressor section 10 via core flowpath 22. Blades14A-14H are disposed within core flowpath 22 generally intermittentlywith stator vanes (not shown). Each blade 14A-14H is connected to onecorresponding disk 16A-16H. The upper portion of disks 16A-16H at theconnection with blades 14A-14H comprises a platform that forms a wall ofcore flowpath 22.

Disks 16A-16H are connected to, and rotate, with shaft 18. Disks 16A-16Hextend radially inward from blades 14A-14H into bore 24 and terminateadjacent engine centerline C_(L) and shaft 18. Vortex reducing device 20is connected to disk 16G and is disposed within compressor diskinterspace 26G. In other embodiments, multiple vortex reducing devicesmay be utilized in one or more compressor disk interspaces.

Blades 14A-14H and vanes (not shown) of high pressure compressor 10 workto incrementally increase the pressure and temperature of air passingalong core flowpath 22 in a manner know in the art. Air is bled fromcore flowpath 22 and a portion of this bleed air passes through vortexreducing device 20 to achieve a desired temperature and pressure profilewithin the gas turbine engine 12 for performance purposes.

As will be elaborated upon subsequently, the present applicationdescribes various embodiments of vortex reducing device 20. Vortexreducing device 20 can comprise a single assembly, for example aweldment, which significantly reduces the number of parts and weight ofvortex reducing device 20 relative to prior art anti-vortex tubes.Additionally, vortex reducing device 20 does not utilize tubes in themanner associated with the prior art but rather utilizes a paddle andretainer with circumferentially spaced slots. This configurationsimplifies the assembly/disassembly and installation processes forvortex reducing device 20.

FIG. 2 shows an enlarged sectional view of one embodiment of vortexreducing device 20 mating with disk 16G. FIG. 3 gives a perspective viewof vortex reducing device 20 without illustrating disk 16G. As shown inFIG. 2, disk 16G includes a tab projection 28. Vortex reducing device 20includes a retainer 30, paddles 32, and a snap ring 34. The retainer 30includes a flange 36 with a groove 38. Paddles 32 include a main body 40and a base 42 with an aperture 44 therethrough. Retainer 30 includes aplurality of circumferentially spaced slots 46.

Tab projection 28 extends from disk 16G in a middle portion thereof toabut and connect to retainer 30 via groove 38 on flange 36. Inparticular, tab projection 28 is adapted to connect to groove 38 viaconventional techniques such as snap fitting. Friction between tabprojection 28 and retainer 30 keeps vortex reducing device 20 frommoving relative to disk 16G leaving retainer 30 coupled to disk 16G.

In one embodiment, retainer 30 comprises an arcuate ring that extendsentirely around the engine centerline C_(L) and shaft 18 (FIG. 1).Paddles 32 (only a single paddle is illustrated in FIG. 2) arecircumferentially spaced about retainer 30 and are received in retainer30. Paddles 32 are circumferentially spaced about the retainer 30 andextend outward thereform. In particular, paddles 32 are disposed toextend radially outward from retainer 30 (as defined with respect to theaxis of symmetry S). Each paddle 32 is disposed between adjacent slots46. Paddles 32 can be attached to retainer 30 by conventional means. Inone embodiment, each paddle 32 is welded (by e.g., electron beam,inertia bond, or friction) to retainer 30 and extends outward therefrominto compressor disk interspace 26G. Snap ring 34 is attached to theinner radial surface of the retainer 30 (with respect to the enginecenterline C_(L)) and is used to prevent paddles 32 from rotating onceinstalled. Flange 36 extends from an outer axial portion of retainer 30to contact tab projection 28 along groove 38.

Main body 40 of paddle 32 extends from retainer 30 into compressor diskinterspace 26G. In the embodiment shown in FIGS. 2 and 3, the outwardextending portion of main body 40 has a semi-circular shape. The concaveportion of main body 40 is illustrated in FIG. 2 between first edge 41Aand second edge 41B. Main body 40 extends through a receiving hole inretainer 30 and transitions to base 42. Base 42 is larger than receivinghole in retainer 30 and is slightly non-circular in shape having a flatportion that allows snap ring 34 to be attached between retainer 30 andbase 42. Main body 40 and/or base 42 can be attached to retainer 30 viavarious means know in the art such as welding, snapping, or pressing. Inthe embodiment shown in FIGS. 2 and 3, paddle 32 defines aperture 44,which extends through base 42. Aperture 44 allows bleed air through theretainer 30 to bore 24 of the gas turbine engine 10 (FIG. 1). In otherembodiments, vortex reducing device 20 does not utilize apertures 44. Inyet other embodiments, apertures 44 extend through the retainer 30 andpaddles 32.

FIG. 3A shows an enlarged perspective view of a portion of vortexreducing device 20 of FIGS. 2 and 3. In addition to elements describedin FIGS. 2 and 3, vortex reducing device 20 includes radii R.

Each slot 46 terminates with radii R adjacent paddle 32. The size ofradii R varies with various embodiments of vortex reducing device 20. Inone embodiment, radii R is between 100 mil (2.54 mm) to 1 inch (25.4mm). Slots 46 allow bleed air through the retainer 30 to bore 24 of thegas turbine engine 10 (FIG. 1). Slots 46, and indeed paddles 32, canvary in size, shape, and number depending on the temperature andpressure profile that is desired to be achieved within the gas turbineengine 12 for performance purposes. The size, shape, and number ofpaddles 32 and slots 46 can also be influenced by thermal/mechanicalstresses on the paddles 32 and retainer 30.

FIG. 4 shows a perspective view of another embodiment of vortex reducingdevice 20. FIG. 4A shows an enlarged perspective view of a portion ofvortex reducing device 20 of FIG. 4. The embodiment shown in FIGS. 4 and4A includes paddles 32 with fillets F.

Paddles 32 are attached to the outer circumference of retainer 30 usingconventional methods such as welding, forging, snapping, riveting, orfastening. In one embodiment, paddles 32 are welded (by e.g., electronbeam, inertia bond, or friction) to retainer 30. Paddles 32 are disposedbetween slots 46 and each paddle 32 has fillet F near the connectionwith retainer 30. The size of fillet F can vary based on designcriteria. In one embodiment, fillet F is between 50 mils (1.27 mm) and0.5 inch (12.7 mm). Similarly, radii R illustrated in FIGS. 4 and 4A canvary based upon design criteria.

As illustrated in FIGS. 4 and 4A, the portion of the paddle 32 thatextends outward from retainer 30 and has a flat cross-sectional shape(i.e., paddle 32 does not have a concave/convex shape as do the paddles32 shown in FIGS. 2 and 3) between first edge 41A and second edge 41B.Retainer 30 does not include holes for receiving paddles 32, insteadpaddles 32 spaced circumferentially apart and connect directly to theouter radial surface of the retainer 30 (as defined with respect to theaxis of symmetry S of retainer 30). As described herein, slots 46 allowbleed air through the retainer 30 to bore 24 of the gas turbine engine10 (FIG. 1).

FIG. 5 shows a perspective view of yet another embodiment of vortexreducing device 20. FIG. 5A shows an enlarged perspective view of aportion of vortex reducing device 20 of FIG. 5. The embodiment shown inFIGS. 5 and 5A includes paddles 32 with fillets F. In particular, thefillets F are disposed near the connection between an inner radialportion (with respect to the axis of symmetry S) of main body 40 of eachpaddle 32.

Paddles 32 are attached to the outer circumference of retainer 30 usingconventional methods such as welding, forging, snapping, riveting, orfastening. Paddles 32 are disposed between slots 46 and each paddle 32has fillet F near the connection between an inner radial portion of mainbody 40 and retainer 30. The size of fillet F can vary based on designcriteria. In one embodiment, fillet F is between 50 mils (1.27 mm) and0.5 inch (12.7 mm). Similarly, radii R illustrated in FIGS. 5 and 5A canvary based upon design criteria.

The inner radial portion (with respect to the axis of symmetry S) ofmain body 40 extends outward from retainer 30. The inner radial portionof main body 40 has a circular cross sectional shape, and thus, has nofirst edge 41A and second edge 41B. However, the outer radial portion ofmain body 40 has a semi-circular shape with a concave portion extendingbetween first edge 41A and second edge 41B. Main body 40 connects toretainer 30 and partially defines each individual aperture 44, whichextends through both main body 40 and retainer 30. Thus, apertures 44are disposed immediately adjacent the base of the paddles 32 and allowbleed air through the retainer 30 to bore 24 of the gas turbine engine10 (FIG. 1) along with slots 46.

In yet other embodiments, paddles 32 may have various geometries asdesign criteria dictate. For example, paddles 32 may have geometriesthat are known in the art of impeller technology to facilitate adequatebleed air passage through slots 46 in retainer 30. In such examples,first edge 41A and second edge 41B could be rotated to various angleswith respect to the axis of symmetry S of the retainer 30 and with oneanother. Paddles 32 could also be aligned, offset, tilted, sloped, orotherwise shaped and disposed at various angles with respect to oneanother and/or the axis of symmetry S of the retainer 30 to facilitateadequate bleed air passage through slots 46.

While the invention has been described with reference to an exemplaryembodiment(s), it will be understood by those skilled in the art thatvarious changes may be made and equivalents may be substituted forelements thereof without departing from the scope of the invention. Inaddition, many modifications may be made to adapt a particular situationor material to the teachings of the invention without departing from theessential scope thereof. Therefore, it is intended that the inventionnot be limited to the particular embodiment(s) disclosed, but that theinvention will include all embodiments falling within the scope of theappended claims.

1. A vortex reducing device for a gas turbine engine, comprising: anarcuate retainer with a plurality of circumferentially spaced slotsextending therethrough; and a plurality of paddles circumferentiallyspaced about the retainer to extend outward therefrom, each paddle isdisposed between adjacent slots.
 2. The device of claim 1, wherein theretainer comprises a ring extending 360° about an axis of symmetry andthe paddle extends from the retainer radially outward away from the axisof symmetry of the retainer, and wherein the plurality of slots allowfor passage of air to a bore of the gas turbine engine.
 3. The device ofclaim 1, wherein the paddle is electron beam, inertia bond, or frictionwelded to the retainer.
 4. The device of claim 1, wherein an outwardextending main body portion of the paddle has a semi-circularcross-sectional shape.
 5. The device of claim 4, wherein the paddledefines or is disposed adjacent to an aperture that extends through theretainer or paddle.
 6. The device of claim 4, wherein the paddle extendsthrough an aperture in the retainer and has a base that is larger thanthe aperture.
 7. The device of claim 6, further comprising a snap ringthat connects to the retainer to prevent the paddle from rotating. 8.The device of claim 1, wherein an outward extending main body portion ofthe paddle has a flat cross-sectional shape.
 9. A vortex reducing deviceassembled within compressor of a gas turbine engine, the assemblycomprising: a first disk and a second disk, each disk extending fromadjacent core flowpath into a bore of the gas turbine engine and forminga compressor disk interspace therebetween, the first disk having a tabprojection on a middle portion thereof; an arcuate retainer with aplurality of circumferentially spaced slots extending therethrough; anda plurality of paddles circumferentially spaced about the retainer toextend outward therefrom, each paddle is disposed between adjacentslots.
 10. The assembly of claim 9, wherein the retainer has a groovethat is adapted to be snap fit into the tab projection.
 11. The assemblyof claim 9, wherein the paddle rotates with the first disk and a bleedair from the core flowpath passes through the first slot and the secondslot to the bore of the gas turbine engine.
 12. The assembly of claim 9,wherein the retainer comprises a ring that is disposed about acenterline of the gas turbine engine and the paddle extends from theretainer outward away from the centerline within the compressor diskinterspace.
 13. The assembly of claim 9, wherein an outward extendingmain body portion of the paddle has a semi-circular cross-sectionalshape.
 14. The assembly of claim 13, wherein the paddle defines or isdisposed adjacent to an aperture that extends through the retainer orpaddle.
 15. The assembly of claim 9, wherein an outward extending mainbody portion of the paddle has a flat cross-sectional shape.
 16. A rotorportion of a high pressure compressor for a gas turbine engine,comprising: a plurality of blades disposed within a core flowpath of thegas turbine engine; a plurality of disks, each disk connected to one ofthe plurality of blades and extending from the blade into a bore of thegas turbine engine; a retainer connected at least one of the pluralityof disks and having a plurality of circumferentially spaced slotsextending therethrough; and a plurality of paddles circumferentiallyspaced about the retainer to extend outward therefrom, each paddle isdisposed between adjacent slots; wherein the paddle rotates with the atleast one of the plurality of disks and a bleed air from the coreflowpath passes through the first slot and the second slot to a bore ofthe gas turbine engine.
 17. The compressor of claim 16, wherein the atleast one of the plurality of disks has a tab projection and theretainer has a groove that is adapted to be snap fit into the tabprojection.
 18. The compressor of claim 16, wherein the retainercomprises a ring that is disposed fully about a centerline of the gasturbine engine and the paddle extends from the retainer radially outwardaway from the centerline.